In general, a number of systems for the electronic input of graphical elements comprising a substantially pen-shaped device exist, such as digital pens or dedicated stylus/support sets (or one that is instrumented to locate the tip of the stylus), for example a stylus/touch-screen device set or a stylus/graphics tablet device set (without a screen).
Dedicated stylus/support sets require usage on the said support, which is restrictive, costly and of limited use spatially.
Also known are digital pens as described, for example, in the U.S. Pat. No. 5,902,968, which discloses a digital pen equipped with a triaxial accelerometer and a triaxial gyrometer, and means for filtering the measurements delivered by the accelerometer and the gyrometer. This filtered data is then converted by changing the frame of reference.
U.S. Patent Publication No. 2006/0088215 A1 discloses a handwriting recognition system comprising means that are sensitive to analogue input signals representative of the movement of a handwriting device intended to be held in one hand and sampling means to deliver signals representative of the acceleration of the handwriting device along at least two axes, at a determined capture sampling rate. The system described additionally comprises filtering means for filtering these sampled signals and a classifier for comparison with a template representative of characters formed.
Such systems provide only for recognizing graphical characters in series, but cannot replace a keyboard and mouse.
Specifically, a known electronic pen does not allow the user to use this same pen as a screen pointer management tool even when the user provides an absolute positioning of the tip of the pen. For example, current optical pens implement functions for digitizing handwriting and drawings, i.e. graphical elements, by an optical positioning technology for the trail of the pen tip on an instrumented surface, but these optical pens cannot be used to control the pointer in the air, for example to deliver a presentation.